I/O aware task scheduling for energy harvesting embedded systems with PV and capacitor arrays

Abstract

The system efficiency using an energy generation source is important. The high efficiency can reduce the cost of the system or increase the lifetime of the system operation. The high efficiency can be achieved by a high generating efficiency, a high consumption efficiency or a high transferring efficiency. Conventional maximum power point tracking (MPPT) techniques and multi-core scheduling methods do not consider the transferring efficiency in the multiple load system. This paper presents a generalized technique for the task scheduling of a multi-core processor considering the transferring efficiency in multiple loads. The target system contains a functionality for dynamic reconfiguration of a photovoltaic/supercapacitor array to change the input voltage of DC-DC converters in multiple loads. The proposed technique minimizes the power loss in the DC-DC converters and charger of the system. Experiments with actual application demonstrate that our approach reduces the energy consumption by 17.7% over the conventional approach, which employs a dynamic voltage and frequency processor.